Former President Barack Obama on Friday combined mockery and outrage as he told the audience at a political rally in Florida about Trump’s move.

“They’re telling you the existential threat to America is a bunch of poor refugees 1,000 miles away,” he said. “They’re even taking our brave troops away from their families for a political stunt at the border. And the men and women of our military deserve better than that.”

Former Obama-era Secretary of Defense and Republican Sen. Chuck Hagel told CNN on Thursday that Trump’s move “is folly. This is political distraction of the highest magnitude.”

Trump is “using our military and our troops in a very political way that … really casts a lot questions about the competency of his leadership,” Hagel said

He continued: “I know the kinds of sacrifices these men and women are involved with every day, and their families. To use them as political pawns like this for a complete fabrication is really wrong.”

Rep. Adam Smith, the ranking Democrat on the House Armed Services Committee, told the Washington Post’s Greg Sargent that a Democratic House would hold hearings on the decision.

“We would ask the Pentagon to come in and explain to us in an open public hearing what they’re doing and why,” Smith told Sargent. “I don’t think we should let the president get away with this type of policy with no justification and no explanation for it.”

A letter from Smith, three other Democrats who would take over top House investigative committees, and 104 of their colleagues to Defense Secretary Jim Mattis demands an explanation, while asserting that “This effort is nothing short of a militarization of the southern border to score political points and stoke misleading fears among Americans regarding immigrants.”

Meanwhile, Newsweek reporters James Laporta, Nicole Goodkind and Chantal Da Silva found that “multiple Pentagon sources” say the move “took officials by surprise, with many senior-level Defense Department officers saying they believed the move was politically motivated and a waste of money.”

“There is no practical or tactical reason for this to happen,” one source told Newsweek.

Defense Secretary Jim Mattis has left no doubt that his top priority as leader of the military is making it more “lethal” — better at war and more prepared for it — and yet nothing about the military’s new mission at the U.S.-Mexico border advances that goal. Some argue it detracts from it.

They also quote James Stavridis, a retired Navy admiral and former head of U.S. Southern Command, saying the troops should be preparing for combat and other missions, “not monitoring a peaceful border.”